CL_SALV_TREE save layout

Hello all,

I am working with the CL_SALV_TREE, in which I display a tree. Now I have implemented the SALV_FUNCTION for LAYOUT.

If I click the layout button, there is no posibility to save the user spezified layout.

Also at the context menu of the layout group ist no entry for save.

I have set the buttons with the following code:

data: mr_tree   type ref to cl_salv_tree.

* first I create a tree correctly.

  mr_tree->set_screen_status(
    pfstatus      =  i_pfstatus
    report        =  sy-repid
    set_functions =  mr_tree->c_functions_all ).

  mr_functions = mr_tree->get_functions( ).
  mr_functions->set_all( abap_true ).
  mr_functions->set_layout_change( abap_true ).
  mr_functions->set_layout_load( abap_true ).
  mr_functions->set_layout_save( abap_true ).
  mr_functions->set_print_view( abap_false ).
  mr_functions->set_find( abap_false ).
  mr_functions->set_group_aggregation( abap_false ).

I set the layout with the following function:

data: ls_key       type SALV_S_LAYOUT_KEY,
        ls_layout    type SALV_S_LAYOUT.

  if not mr_layout is bound.

    mr_layout = mr_tree->get_layout( ).

    ls_key-report = m_repid.

    mr_layout->set_key( ls_key ).

    mr_layout->set_default( abap_true ).

    mr_layout->set_save_restriction( 3 ).

    mr_layout->set_initial_layout( space ).

  endif.

Can sombody tell me, why I can't save the layout in combination with the CL_SALV_TREE class???

Yours Joerg